New York City's Ziegfeld Theatre on Monday night was generously drenched in music and emotion, both high and low — the very elements that are dulled and disdained in Lois Lowry's beloved young-adult novel The Giver. The film adaptation's cast and creative team were celebrating the 20-year journey to bring Jonas, Fiona and their dystopian community to the big screen at its world premiere.

Just over an hour before the screening began, news of Robin Williams' death reached the filmmakers, triggering a salute from Jeff Bridges, who co-starred in TheFisher King with the late actor. "I am filled with such mixed emotions tonight," said Bridges when introducing The Giver, noting the irony of his title role as being the emotional leader of the community. "It's very difficult for me to be here with all these emotions and feelings — wonderful, I must say, but as with many elements in life, there is an underbelly, and we're losing a dear, dear friend, Robin Williams. Such a brilliant human being. My heart goes out to his family." He then looked toward the Ziegfeld ceiling and laughed, "I feel Robin coming in now, he says, 'Get on with it, Bridges! On with the show!'"

Before introducing Bridges, Harvey Weinstein briefly recalled making Good Will Hunting with Williams: "I promise you, if he were onstage, he'd want the party to continue and continue and continue. He is well missed and well loved, and whatever the circumstances are, he was a giant in our industry and more importantly, a great man."

Also on hand at the world premiere were Meryl Streep, Katie Holmes and Taylor Swift, each of whom crossed to the fan-lined side of 54th Street to sign autographs and pose for selfies. The Weinstein Company and Walden Media teamed with Fathom Events to stream the red-carpet premiere to more than 250 theaters across the country, also allowing audiences to see the film ahead of its official release. The screening kicked off with a performance by OneRepublic of the film's song "Ordinary Human," which was initially pitched to frontman Ryan Tedder by executive producer Scooter Braun, as both are longtime fan of the book. "I wanted to see how the end of the whole journey would translate on film, because you're not really sure in the book, if that's real, " he told THR of the ending. "You want to be optimistic as a kid that it's all OK!"

The 1993 Newberry Medal-winning book follows Jonas, a young boy who was born into a seemingly ideal, if colorless, community of conformity and is assigned as its Receiver of Memories. As he undergoes training with The Giver (Bridges), who carries all of the society's forgotten facets, he learns about the dark sides of the supposed "utopia" of Sameness.

With the film being "18 years in the making!" as Bridges enthusiastically shouted before the screening, its final screenplay resulted from combining a 1996-97 draft by Robert B. Weide and a recent run by Michael Mitnick. "Even though Michael and I had never met [until this week], and our scripts were 17 years apart, I read the final draft and it felt like a true collaboration, as thought we had sat side-by-side at a computer together — I was very pleased," said Weide.

Die-hard fans of the novel have expressed their concerns about the decision to make the characters older. Producer Nikki Silver credits The Weinstein Co. for the strategic move: "We started to see that the book would appeal on the wider audience basis." Mitnick, who first read the book in elementary school, said, "It was part of the realities of getting the movie made, but we got lucky with these characters who have an arrested emotional development — the fact that they've gone through puberty hasn't made much of a change in their life, as they're still emotionally at zero. You get to see someone going down this slide and it's as though he were 12." Weide also noted, "Everyone, including Lois ultimately, thought it was the right decision."

Another welcome change by Lowry? The onscreen presence of the community's Chief Elder, played by Streep. "It's a very minor role in the book, with not really any personality," she told THR. "She's very complex — Jeff plays the spiritual leader, and she's the political leader, and they each have an agenda. There's conflict, and yet when they each present their side of this issue at the end of the movie, you understand where they're both coming from. Though she's chilling in the role, she becomes sympathetic."

Director Phillip Noyce said of Streep's not-so-villainous presence onscreen: "She's advocating something that's very seductive — a world without pain! Conflict! war! You don't have to wake up to murder and mayhem! It's not that hard to see something in what she's saying, but the way Meryl says it, it's even harder not to accept it because she's convincing."

When asked what they'd miss most from the daily injections the community's residents must receive, Noyce mentioned the memories of his children; actors Odeya Rush and Emma Tremblay noted that they'd both be most incomplete without love; while Brenton Thwaites joked to THR that he'd miss "good waves" most of all. Both the film's writers would miss music most. Yet Swift told Fathom Events on the red carpet that if she were assigned to a role in the community, she'd prefer the caretaker job of Rush's character, Fiona.

Still, the bittersweet evening was one that celebrated the wide appeal of dystopian literature among young adult readers. Said Lowry, "It's the fact that a young person can make a difference in the world — here's a young boy who perceives the hypocrisy of the governing body, and seeks to change things. There's an image in the memories that he receives of the young man in front of the tank and Tiananmen Square — that's not in the book, and when I saw that, it sent shivers up my spine. That's what the boy represents."

Following the premiere, the stars headed uptown to the Central Park Boathouse for the afterparty. Out on the lakeside courtyard, Holmes was spotted congratulating her onscreen daughter Tremblay on a job well done, while Thwaites, Rush and Cameron Monaghan entertained guests alongside Weinstein, Tedder and Braun.